Clustering setup

I was looking at the demo, and while setting up a cluster (I understand it won’t work on the demo), I noticed this as a pre-requisite :

One or more InterWorx-CP clustered servers on the same segment

Does this mean IP’s on a different Class C, on the same network, cannot be used as computing/clustered nodes?

I think that it would technically work, but we suggest it because it correlates with physical proximity, which would lower latency issues.